This animation illustrates how water flows from the middle of the United States down to the Mississippi River. Much of the nutrients, fertilizers and pollution that impact the health of the Mississippi River and Gulf of Mexico originate far up stream This sequence begins with a NASA satellite image of the United States. Then, the sequence highlights the Mississippi River. The sequence shows all the tributaries that feed into the Mississippi River. From there the animation expands to the whole drainage basin, everything between the Rockies and Appalachian Mountains drains through the Mississippi River. The concept of a watershed demonstates how human activities far from the ocean can have dramatic impact on life in the sea. Note: This is the standard definition version of the Mississippi River Water Basin animation MPWG. Animator: Susan Twardy (HTSI). Scientist: Gene Feldman (NASA/GSFC). Writer: Rani Chohan (NASA/GSFC).